Lower-grade gliomas have highly variable clinical behavior that is not adequately predicted on the basis of histologic class. Consequently, clinicians increasingly rely on genetic classification to guide clinical decision making. Mutations in IDH1 and IDH2 characterize the majority of lower-grade gliomas in adults and define a subtype that is associated with a favorable prognosis. Mutations of the telomerase reverse transcriptase (TERT) promoter, which result in enhanced telomerase activity and lengthened telomeres, have been observed in several human cancers including glioma. Accumulating evidence suggest that TERT promoter mutation is another molecular marker which can stratify lower-grade gliomas into prognostic subgroups in combination with IDH mutation. In our previous study, patients(28/377, 7.4%) who had lower-grade gliomas with IDH wild-type (IDH-wt) and TERT promoter mutation (TERTp-mut) had the poorest clinical outcomes (median OS, 27.7mo; 5-year OS, 29%). These results were accordant with the recent studies and suggested that current treatment strategies are not adequate for this subtype of lower-grade glioma.